Altering the course of U.S social policy, Maine and Maryland became the first states to approve same-sex marriage by popular vote, while Washington state and Colorado set up a showdown with federal authorities by legalizing recreational use of marijuana.

The outcomes for those ballot measures Tuesday were a milestone for persistent but often thwarted advocacy groups and activists who for decades have pressed the causes of gay rights and drug decriminalization.

"Today the state of Washington looked at 70 years of marijuana prohibition and said it's time for a new approach," said Alison Holcomb, manager of the campaign that won passage of Initiative 502 in Washington.